1. The size and thickness of the PCB board must be consistent with the specified appearance size and thickness, and there must be no deviation. The surface of the circuit board is free of defects, deformation, shedding, scratches, open circuits, short circuits, oxidized white, yellow, dirty or excessively etched traces, free of dirt, copper particles and other impurities.
2. The ink covering layer is uniform, bright, without falling off, scratches, copper dew, deviation, printing plate, etc.
3. The symbols and letters in the screen printing are clear, without omissions, ambiguities, reversals, deviations and other undesirable phenomena.
4. The carbon film must not have defects, deviations, short circuits, open circuits, reverse printing, etc.
5. PCB bottom plate molding, no leakage, deviation, hole collapse, piercing, plug hole, beer burst, beer reverse, crushing and other phenomena.
6. Whether the edge of the PCB is smooth, if it is a V-shaped cutting process, you should pay attention to whether the V-shaped cutting groove causes breakage, whether the two sides are symmetrical, etc.